Gearing.



@NIT S RUDOLIEI-I C. SCHEBLING, 0F CHICAGO', ILLINOIS, ASSIG-NOR TOHENRY E. BULLOCK AND JAMES E. BULLOCK, IBOII-Iy OF CHICAGO, ILLINOIS.

GEARING.

Specification of Letters Patent.

Patented Aug. 2d, 1915.

Applicationfled October 8, 1914'. Serial No. 865,631.

T0 all whom it may concern.'

Be it known that I, RUnoLrH C. Sonna- LING, a citizen of the UnitedStates, and resident of Chicago, in the county of Cook and State ofIllinois, haveinvented certain new and useful Improvements in Gearing;and I do hereby declare that the following description of my saidinvention, taken in connection with the accompanying' sheet of drawings,forms a full, clear, and exact specification, which will enable othersskilled in the art to which my said invention appertains to make and usethe same.

This invention has general reference to gearing, and speciiically to theso-called class of mutilated gears which are designed to intermittentlyrotate the driven member of such gears. In this class of gearing thereis always considerable danger of breaking one or more of the gear teethcaused by the impact of the gear teeth when the driven member issuddenly caused to rotate owing to the inertia ofthe mass which has tobe immediately started from a condition of rest to one of motion, whichis extremely severe on the first or entrance teeth of a teethsection ofthe driving gear.

The object of my invention is to remove, or at least to-a great extentavoid this breakage of gear teeth.

Other objects of this invention will hereinafter fully appear.

In the drawings already referred to, which serve to illustrate thepreferred embodiment of this invention, Figure 1 is an elevation of aset of gearing embodying my invention. Fig. 2 is an end-elevation of thesame, like characters of reference being used in both figures todesignate the same parts.

A indicates a so-called mutilated spur gear wheel, z'. e., a wheelhaving in its face a multiplicity of sections of gear teeth interruptedby blank spaces between the gear teeth sections. In the drawings I haveshown two such gear-teeth sections and two of the blank spaces, but itis evident, that only a single teeth section and a single blank sectionmay be employed, without departing from the scope of my invention.

Inasmuch as the gear sections and the blank spaces, when more than oneof these sections are employed are alike, I shall conline thisdescription to only one of these elements.

12 designates the rim of the spur gear wheel A, which is assumed to bethe driver of a pair of coasting gear wheels, B, being the driven memberor pinion. rlhis rim has on its face a section or series of cogs orteeth, 13, and a blank section 14, whereby the pinion B is caused tointermittently rotate while the driving gear is making one revolution,the number of revolutions of the pinion in one cycle depending upon theratio of the gear-wheels; and the duration of rest, upon the length ofthe blank space between a jacent teeth sections. rllhe spurgear wheelis, preferably, keyed to the shaft 15; and the pinion B is eitherfastened to, or formed integrally with, a shaft 16, both shafts beingconstructed to rotate in suitable bearings, not shown.

17 designates a stud or pin projecting from the Hank of the rim 12. Itslocation is adjacent to the first or entrance tooth 1S of atooth-section 13, and it is either formed integral with the rim 12, ormade separa-te therefrom and secured to the flank of the rim by anysuitable means, 19, such as shown in Fig. l.

2O designates a cam comprising a multiplicity of curved arms, 21, 21a,said cam being secured to the shaft 16 of the pinion in any approvedmanner. The concave portions 21, 21a, of this cam constitute theoperating faces; and the curvature thereof is such that when thespur-wheel is rotated, the pin 17 will strike one of said arms at itsroot to initiate the rotation of the pinion at a speed slightly inexcess of the actual rotative speed of said pinion, the relativeposition of the cam and the gear teeth of the two gear wheels being-suchthat the first tooth 22 of the pinion touches the first entrance tooth13, of the spur gear at its rear flank, so that the teeth enter easilyinto mesh with each other. rlhe curvature of the cam is such, however,that, as the pinion with its cam rotates and the pin 17 slides on theconcave face of the cam, the speed of the pinion slightly increases sothat the second tooth 23 of the pinion will contact with the third tooth24 of the spur-gear at the front flank of the latter, after which therotation of the pinion will be continued by the teeth section 13. Inthis manner the teeth of the pinion enter into mesh with those of thespur gear wheel without any ar or blow so that breakage of these teethis, if not entirely overcome, at least considerably lessened. The

cam 20 is preferably made from a quality of steel possessing greattensile strength combined with the highest degree of ductility; and thepin 17 is preferably constructed from the same material. Both of theseelements are also preferably surface hardened to resist wear as much aspossible.

I have shown the cam 20 provided with two curved arms 21. Thisconstruction is desirable in case where the ratio of the gearwheelsteeth is a multiple of the pinion-gear teeth plus one-half, 0r in otherwords, where a pinion has, say 10 teeth, and the teeth section 13 has 15teeth. This proviso is required in order to assure that a cam-arm isalways in proper position to gradually lead the gear teeth intoy mesh.

In a mechanism of the type described, it is preferable that the pinionor driven member of the gear-train always stops in the proper positionfor engagement with the starting mechanism described, which, owing tothe inertia of the rotating parts driven by the pinion, it might notalways do when the driven member separates from the driving means. Tosecure this positive stopping of the rotation of the driven member atthe correct position, I prefer to form on the rim of the spur gear,adjacent to the blank section 14:. a curved track 25, concentric withthe shaft 15, and approximately even with the crowns of the teeth in theteeth section. This track projects from the flank of the spur-wheel; andon the pinion shaft 16, adjacent to the pinion B, I form a slide 26,either secured to, or formed integrally with said pinion B. This slidehas curved faces corresponding to the curvature of the track, and itrotates with the said pinion; but, as soon as the forward terminal 27 ofsaid track reaches the pinion, the slide 26 will strike this track andstop the pinion and also prevent any accidental rotative movement ofsaid pinion until the rear terminal 28 of said track passes said slideand liberates the same at the moment when the auxiliary startingmechanism described initiates the rotation of the driven member of thegearing.

Having thus fully described this invention and disclosed the preferredembodiment thereof, I claim- 1. In gearing, the combination, of amutilated gear wheel, a driven member connected to, and constructed tobe intermittently rotated by said mutilated gear wheel, and meansconstructed to initiate the rotative movement of said driven member,said latter means including an auxiliary driving element on saidmutilated gear wheel, and an arm on said driven member, said arm havinga concave contacting face to impart to said driven member a differentialrotative movement.

2. In gearing, the combination, of a mutilated gear wheel, a gear pinionconnected to, and constructed to be intermittently operated by saidmutilated gear wheel, means, constructed to initiate the rotativemovement of said gear pinion, said means including auxiliary drivingelements on said mutilated gear wheel and arms on said gear pinion, saidarms having concave, curved,

contacting faces constructed for engagement with said auxiliary drivingelement to impart a differential rotative movement to the latter shaftin alinement with the toothsegment aforesaid, a slidable element fixedto the flank of said gear pinion in alinement with `said curved track, acam in front of said slidable element, said caml having curved arms, anda stud projecting from the flank of said spur gear wheel and constructedto engage one of the curved arms of said cam at the concave side of saidarm, said stud being located adjacent to the entrance-teeth of said spurgear wheel teetl section.

In testimony that I claim the foregoing as my invention, I have hereuntoset my hand this 5th day of October, 19111, in the presence of twosubscribing witnesses.

RUDLPH C. SCHERLING.

Witnesses: v

MICHAEL J. STARK, JOHN B. SMITH.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C.

